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Abstract: The recently synthesized regio‐regular poly(3‐hexylthiophene‐2,5‐diyl) selectively deuterated on the main chain backbone and/or on the hexyl side chain have given the opportunity to record their infrared (IR) and Raman spectra, and to carry out a spectroscopic study supported by density functional theory calculations. The Effective Conjugation Coordinate associated with the collective C=C stretching mode, with Raman scattering and IR absorption near 1,450 cm−1, is used as a probe of the electronic structure and the molecular conformation of the chain backbone. With the help of the data collected from the deuterated species, the vibrational assignment for the structurally relevant 1,600–1,300 cm−1 region has been clarified. The excitation‐dependent wavenumbers and intensities of the C=C stretching Raman modes are discussed. Raman spectra excited in‐resonance or off‐resonance show the existence of a multimodal distribution of effective conjugation lengths that are ascribed to a phase hairy‐A with a practically flat backbone chain, a phase hairy‐B where the conformation of the backbone is slightly distorted, and an amorphous phase. IR spectra provide additional information on the Effective Conjugation Coordinate. [ABSTRACT FROM AUTHOR] more...

Inversion of the connections of amidine linkers combined with controlled oligothiophene chain catenation in oligothiophene-naphthalimide assemblies provides an efficient method to tune the HOMO and LUMO values in this type of assemblies. This modification also suppresses the intramolecular charge transfer (ICT) band normally found in this type of derivatives, also delocalizing the frontier molecular orbitals over the whole conjugated skeleton. The resultant assemblies were used in the fabrication of field-effect transistors, which showed well-balanced ambipolar transport. [ABSTRACT FROM AUTHOR] more...

The synthesis, characterization, and optical properties of a novel star-shaped oligothiophene with a central rigid trithienobenzene (BTT) core and diketopyrrolopyrrole (DPP) units are reported and compared with homologous linear systems based on the benzodithiophene (BDT) and the naphthodithiophene (NDT) units end capped with DPPs. This comparison is aimed at elucidating the effect of the star-shaped configuration versus linear conformation on the optical and electrical properties. Electronic and vibrational spectroscopies, together with transient absorption spectroscopy, scanning electronic microscopy, and DFT calculations are used to understand not only the molecular properties of these semiconductors, but also to analyze the supramolecular aggregation in these derivatives. We conclude that although the subject star-shaped derivative is not optimal in terms of π-conjugation, its extended BTT unit significantly favors intermolecular π-stacking interactions, which is interesting for their applications in devices. Field-effect transistors and solar cells were fabricated with these new molecular semiconductors and the performance difference discussed. [ABSTRACT FROM AUTHOR] more...

π-conjugated polymers based on the electron-neutral alkoxy-functionalized thienyl-vinylene (TVTOEt) building-block co-polymerized, with either BDT (benzodithiophene) or T2 (dithiophene) donor blocks, or NDI (naphthalenediimide) as an acceptor block, are synthesized and characterized. The effect of BDT and NDI substituents (alkyl vs alkoxy or linear vs branched) on the polymer performance in organic thin film transistors (OTFTs) and all-polymer organic photovoltaic (OPV) cells is reported. Co-monomer selection and backbone functionalization substantially modifies the polymer MO energies, thin film morphology, and charge transport properties, as indicated by electrochemistry, optical spectroscopy, X-ray diffraction, AFM, DFT calculations, and TFT response. When polymer P7 is used as an OPV acceptor with PTB7 as a donor, the corresponding blend yields TFTs with ambipolar mobilities of μe = 5.1 × 10−3 cm2 V-1 s-1 and μh = 3.9 × 10−3 cm2 V-1 s-1 in ambient, among the highest mobilities reported to date for all-polymer bulk heterojunction TFTs, and all-polymer solar cells with a power conversion efficiency (PCE) of 1.70%, the highest reported PCE to date for an NDI-polymer acceptor system. The stable transport characteristics in ambient and promising solar cell performance make NDI-type materials promising acceptors for all-polymer solar cell applications. [ABSTRACT FROM AUTHOR] more...

A new family of naphthalimide-fused thienopyrazine derivatives for ambipolar charge transport in organic field-effect transistors is presented. Their electronic and molecular structures were elucidated through optical and vibrational spectroscopy aided by DFT calculations. The results indicate that these compounds have completely planar molecular skeletons which promote good film crystallinity and low reorganization energies for both electron and hole transport. Their performance in organic field-effect transistors is compared with twisted and planar naphthaleneamidine monoimide-fused terthiophenes in order to understand the origin of ambipolarity in this new series of molecular semiconductors. [ABSTRACT FROM AUTHOR] more...

Decreased serum creatinine concentration has been recently described to constitute a new risk factor of type 2 diabetes. Increased free radicals have been consistently associated with decreased serum creatinine and with cellular senescence. Telomere length is considered as a biological marker for senescence. We aimed to study the association of telomere length with serum creatinine. Telomere length of subcutaneous adipose tissue cells was measured in a sample of obese and nonobese subjects (n = 49). Telomere length of subcutaneous adipose tissue cells was positively associated with serum creatinine (r = 0.40, P = 0.004), i.e., the lower the telomere length, the lower the serum creatinine, but not with glomerular filtration rate (GFR). In addition, telomere length was negatively associated with BMI (r = −0.45, P = 0.001) and systolic blood pressure (r = −0.41, P = 0.003). In a multiple linear regression analysis, BMI (P = 0.005), systolic blood pressure (P = 0.01) and telomere length (P = 0.03) independently contributed to 37% of serum creatinine variance after controlling for sex and age. In conclusion, the association of serum creatinine with a marker of cellular senescence suggests an underlying mechanism influencing both decreased serum creatinine and increased risk of type 2 diabetes. [ABSTRACT FROM AUTHOR] more...

We report the ultraviolet (UV)-Vis, Fourier transform-infrared (FT-IR), and FT-Raman spectroscopic study of an electrogenerated chemiluminescence (ECL) emitting compound containing two electron-accepting phenylquinoline end groups covalently attached to an electron-donating 10-methylphenothiazine central moiety. The optimized molecular geometry of the neutral compound as determined from quantum chemical density functional theory (DFT)//B3LYP/3-21G* calculations shows that the phenyl groups appended onto the quinolines are twisted by ≈62° from these moieties. The sulfur atom is also tilted with respect to the plane defined by the phenyl rings of the phenothiazine, in both the neutral and singly oxidized species. The highest occupied molecular orbitals (HOMO) and lowest unoccupied molecular orbitals (LUMO) of the neutral systems partially overlap, so that the lowest-energy visible absorption band implies a certain degree of charge transfer from the phenothiazine toward the phenylquinolines. In contrast, the removal of the first electron mainly affects the structure and equilibrium charge distribution of the phenothiazine, and much less in those of the quinolines. In addition, the DFT//UB3LYP/3-21G* topologies of the molecular orbitals around the bandgap region of the radical cation reveal no molecular orbital overlap between the two types of constituent building blocks, thus inhibiting the delocalization of the injected positive charge over the whole molecule. This feature could be in line with the ability of this system to generate localized radical ions capable of displaying chemiluminescence upon annihilation, as previously observed experimentally. The UV-Vis and FT-Raman spectra of the singly oxidized species generated upon treatment with FeCl3 in CH2Cl2 solution have also been recorded. The experimental data were interpreted with the help of DFT calculations. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 [ABSTRACT FROM AUTHOR] more...

Simulation and teleoperation tools offer many advantages for the training or learning of technological subjects, such as flexibility in time-tables and student access to expensive and limited equipment. In this paper, we present a new system for simulating and tele-operating robot arms through the Internet, which allows many users to simulate and test positioning commands for a robot by means of a virtual environment, as well as execute the validated commands in a real remote robot of the same characteristics. The main feature of the system is its flexibility in managing different robots or including new robot models and equipment. © 2005 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR] more...

The frequency of the serum atypical pseudocholinesterase variant was significantly higher (p <0.005) in a group of 115 lepromatous leprosy patients than in a comparison group of 133 healthy individuals, This finding corroborates the results obtained in the group of patients from India, and supports the contention that the serum atypical pseudocholinesterase is one of the possible genetic factors involved in susceptibility to leprosy. [ABSTRACT FROM AUTHOR] more...

Individuals suffering from substance use disorder often experience relapse events that are attributed to drug craving. Insular cortex (IC) function is implicated in processing drug-predictive cues and is thought to be a critical substrate for drug craving, but the downstream neural circuit effectors of the IC that mediate reward processing are poorly described. Here, we uncover the functional connectivity of an IC projection to the ventral bed nucleus of the stria terminalis (vBNST), a portion of the extended amygdala that has been previously shown to modulate dopaminergic activity within the ventral tegmental area (VTA), and investigate the role of this pathway in reward-related behaviors. We utilized ex vivo slice electrophysiology and in vivo optogenetics to examine the functional connectivity of the IC-vBNST projection and bidirectionally control IC-vBNST terminals in various reward-related behavioral paradigms. We hypothesized that the IC recruits mesolimbic dopamine signaling by activating VTA-projecting, vBNST neurons. Using slice electrophysiology, we found that the IC sends a glutamatergic projection onto vBNST-VTA neurons. Photoactivation of IC-vBNST terminals was sufficient to reinforce behavior in a dopamine-dependent manner. Moreover, silencing the IC-vBNST projection was aversive and resulted in anxiety-like behavior without affecting food consumption. This work provides a potential mechanism by which the IC processes exteroceptive triggers that are predictive of reward., (© 2020 Society for the Study of Addiction.) more...

Ultrapotent topical corticosteroids and circumcision are usually effective for male genital lichen sclerosus (MGLSc); however, refractory cases are often referred to our Male Genital Dermatology Unit. Treatment with autologous platelet-rich plasma (TPRP) has recently been advocated as a safe and effective treatment option, but there have been no prospective studies in men to date. The objective of this study is to assess the safety and efficacy of TPRP for MGLSc resistant to conventional therapy. A prospective, open-label, single-arm, therapeutic study was carried out in this study. Inclusion criteria: resistant to conventional therapy for at least 6 months. Procedure: infiltration of 0.1 mL/cm 2 PRP every 8 weeks. Monthly data recording: visual appearance with photographs and external scoring by an expert using Investigator's Global Assessment Scale (IGA scale 0-5), symptoms (scale 0-5), quality of life (QoL; Dermatology Life Quality Index [DLQI]), and complications. No. of patients included was n = 5. No. of patients excluded during treatment was n = 1. Mean initial IGA: 3.6. Mean initial DLQI: 6. TPRP n = 34 (range: 2-9; average: 6.8 per patient). Mean IGA at 18 months: 3.25. Mean DLQI at 18 months: 1.25. All patients reported being completely asymptomatic at 10 months. No. of patients with complications is n = 1 (balanitis). TPRP seems to be safe and effective, regarding symptom control and improvement in QoL; however, visual changes were minimal., (© 2020 Wiley Periodicals LLC.) more...